This invention relates to an improved elevator suitable for handling heavy loads aboard ship and more particularly, to an elevator capable of handling pallet loads weighing up to three thousand pounds.
In my U.S. Pat. No. 4,130,196, I disclosed a package elevator for a ship wherein slotted or tined trays are carried by pairs of forked followers pivotally attached to a pair of chains driven in parallel endless paths by upper driving sprockets and around lower idler sprockets. The elevator is suitable for transporting packages weighing about one hundred eight-five pounds each. The followers have arms on which are mounted follower rollers which project into inner and outer endless guide tracks. The rollers guide the trays so that they lie along the chains when in a return course, but project outwardly therefrom when in a load-carrying mode. The guide tracks include cam blocks adjacent the sprockets which turn the follower arms and trays only ninety degrees relative to the chains as the trays travel around the sprockets.
It is an object of the present invention to provide an elevator for a ship which is suitable for heavier loads than can be accommodated by the elevator disclosed in my aforementioned U.S. Pat. No. 4,130,196.
It is a further object of the present invention to provide an elevator of the aforementioned type which requires a minimum amount of space in which to rotate the trays.
It is a still further object of the present invention to provide an elevator of the aforementioned type wherein the followers and the trays are both symmetrical, such that symmetrical loading on the trays can be achieved, whereby the entire loading is carried axially by the chains and none of the direct loading is carried by the followers or their rollers.
It is a still further object of the present invention to provide an elevator of the aforementioned type which requires only one guide track for the follower rollers on the load-carrying side.
It is a still further object of the present invention to provide an elevator of the aforementioned type wherein the guide tracks for the follower rollers do not cross each other.
It is a still further object of the present invention to provide an elevator of the aforementioned type wherein the cam tracks adjacent the sprockets are substantially identical at both the upper and lower ends.
It is a still further object of the present invention to provide an elevator of the type described which is simpler and more economical to construct than elevators heretofore known.